User-Based Access Control

User-Based Access Control (UBAC) is an access management model that grants or denies permissions directly to individual users rather than roles or groups. Unlike RBAC, where permissions are assigned based on roles, UBAC applies policies that specify access for specific users. Key elements include direct permission assignment, user-based policies, and identity verification. UBAC enables fine-grained control and customization but can be difficult to manage at scale. In Keycloak, UBAC is implemented through user-based policies, attribute-based decisions, and integration with other access control models like RBAC and ABAC. It aligns with Zero Trust by enforcing strict identity verification before granting access.